It has been a chastening campaign for Wales, the champions whose ineffectiveness in chasing a game has cost them. Their comfort in holding on to leads should ensure a seventh successive win over Scotland, but with a two-Test tour to South Africa followed by games against the three major southern hemisphere nations in the autumn, it will not prove much.

A significant difference between Wales and England is the facility the latter have for turning deficits into leads. They have done so four times this season, against New Zealand and France, when at one stage they trailed by 14 and 13 points respectively, and against Australia and Ireland, who both lost after enjoying a seven-point advantage, scoring at least one try each time.

Wales have also tried to come from behind against four opponents, failing to score a try against South Africa, Ireland and England. They threatened only Australia in Cardiff in November, and then in a match when they had been outplayed behind. It may be unfair to label them flat-track bullies, but they are vulnerable in a game of wits.

Wales have, for the most part, maximised their potential in the six years Warren Gatland has been in charge, successful in Europe if not against a southern hemisphere big three whose ability to create and score tries in pressure moments has contrasted with Wales's reliance on the boot of Leigh Halfpenny, who will miss the rest of the season because of injury.

Halfpenny has supplied 72% of Wales's points this tournament: Jonathan Sexton and Owen Farrell's percentages are below 50 and no team is as reliant on their kicker. Dan Biggar will take aim at goal against Scotland in his first Six Nations start since the victory over England in Cardiff a year ago.

"It is a strange feeling for us not having anything to play for," said the fly-half. "We are effectively playing for a position in the top half of the table and we will not need any pumping up after Twickenham. It has been a disappointing defence of our title, but no one should write us off. There is a bit of time between now and the World Cup and we have to make sure we get a scalp in the big games we have later in the year."

Scotland's campaign has been a familiar tale of heartache and woe. Outplayed by the two outstanding teams in the tournament, they defeated Italy and turned their superiority over France into a defeat. They have asked for the Millennium Stadium roof to be closed, even though it has been a week of sunshine in Cardiff, which would indicate they intend to seek width.

Two of Scotland's coaches, Scott Johnson and Jonathan Humphreys, will be returning to Wales, the latter a former captain of the men in red. "Wales will be hurting after losing like that to an old foe," said Johnson. "We have to expect that and match it. Our intent all tournament has been to play rugby and that is why we have asked for the roof to be closed."

Gatland is using the match to gauge his strength in certain positions. Having dropped Mike Phillips to the bench for two matches, the Lions Test front-rowers Richard Hibbard and Adam Jones are among the replacements after a second weak platform provided by the tight five. Wales may take out their frustration on opponents who are stronger than their position suggests, but their real battles lie ahead and they need to react when their gameplan combusts.